silverrotor

iTrader: (1)

I will have a Street Ported, freshly rebuilt s5 TII Motor with my LT8 soon. This will be complimented with a 255 Hi-Flow Walbro, custom TID that will end at the Brake Duct (compliments of my East Bear Headlight Kit that allows for tons of space for this and a future FMIC), followed lastly by a 3" full exhaust with no Cat.

I ask, will I run super lean by maxing out the Fuel Injector's? Can the LT8 allow wnough fuel to my setup using my 550cc FI's? Do you think I will or should have to upgrade my Injectors to bigger ones?

For what It's worth, I just recently had my FI's machine cleaned and the one replaced with a newly cleaned one. Apparently, It had a sticky valve.

rx7_turbo2

Sounds like a good setup.

Running lean will depend on a ton of stuff. Are you running stock turbo? If your running stock turbo at stock boost levels then I don't see a problem. If you want to turn the boost up a bit say to 15psi plus I would have upgraded the injectors, and looked at a new FPR.

I will have a new S4 motor with very large streetport. To4b hybrid turbo. I will be running an FD fuel pump. 680cc primaries, 1600cc secondaries, Paxton FPR, parallel fuel rails.

silverrotor

iTrader: (1)

Thanks for the response...

Yes. I will be running the stock s5 TII Turbo. Atleast for now. I have a HKS EBC aswell that will allow me to raise the boost should I not run lean. Thats my biggest worry now.

I think this Is a sweet setup but don't want to have It short lived. As I mentioned before In another thread, I'm a noob again - since I entered the darkside.

What else should be considered?

TonyTurboII

How about my setup? Stock -RE motor, 4x550s, RB 3in exhaust, stock S5 turbo, and NPR FMIC

Turbo Timmy

Check here to see if you will be ok.
http://www.rx7.com/cgi-local/2ndgencalc.cgi

(put 80 as the percentage)

silverrotor

iTrader: (1)

And It Is working out for you? Sounds very much simular to my set up except I'll have a 13BT with street port. Details please.

silverrotor

iTrader: (1)

I came across this at one point or another. 80 as a percentage for what? ECU Controlled Max Duty Cycle? Max Duty Cycle?

For the 2 above at 80 percent, I only have 253hp.

Turbo Timmy

Ok so you know you could make more hp than that so you just have to limit your boost to stay within the fuel limits. Probably keep it 6-8psi?

silverrotor

iTrader: (1)

Or Increase the Boost...until leaning occurs. Yah. I just wanted to get a hypothesize. Thanks for the link.

rx7_turbo2

I think that calculator is a little conservative. The Max HP number can be increased by using a larger fuel pump and raising the fuel rail pressure. However Silverrotor I would not raise boost much past 10-11psi with the stock injectors, even with a Walbro. But that's just me.

silverrotor

iTrader: (1)

Also, If I am running a TMIC too, I'd limit Boost to no more than 10-12. I'd think with the conservative number tabulated through your link, that having a standalone EMS would compensate for much more HP. I remember Brandon saying that the removal of the AFM, In conjunction with the MT LT8, would be good for 20-30 hp. Again, don't quote me on that.

Ryde _Or_Die

Personally I'd go with some 720s in the secondaries to be safe. You will have the capability to tune them down easily with the LT-8 and it will make things much easier to up the boost, and much safer at the same time.

And rx7_turbo2:

I assume you have a microtech as well correct? Are you planning on getting a whole new larger turbo in the future? Because I have the same setup as you and am running pretty rich with just 720s in the secondaries.

rx7_turbo2

I agree 100%

Yup I have an LT8. I do plan on a bigger turbo in the near future. Chris Ng on this forum runs the same turbo with 720 primaries and 1600 secondaries controlled with a Wolf 3d, it controls the fuel just fine. I am going to be breaking a new motor in with the microtech, so I will use 550 primaries and 680 secondaries with the FD pump to do that. I figure it should work fine for break in. Then once the motors broken in I will swap in the 1600's and tune it with a wideband.

silverrotor

iTrader: (1)

Glad to have all this Info. At a later date, where would be the best place to get a deal on 720s?

Ryde _Or_Die

Ya, your way is fine. Just wanted to make sure you know that with your current hybrid you will have a helluva lot of fuel

Ryde _Or_Die

I got mine for $110 a piece from rx7store.net but I have seen some used ones for about half that lately.

TonyTurboII

Havent started it yet. Im waiting for a local shop to finish making my IC piping.

silverrotor

iTrader: (1)

Just an after thought...With my proposed set, won't I be seeing higher than normal boost levels? ie dangerous levels, possibly maxing out the 550 FI's?

I think now, come to think of It, this Is why I posed the Initial question.

rx7_turbo2

Ok, there is no point in dicking around. Bigger injectors are better than injectors that are too small. If your concerned about it get bigger injectors.